Women feel their absolute sexiest in flattering underwear. Treat her to some new lingerie you have picked together. The more comfortable she is in a slightly weird situation the better the sex will be, so think of it as a sexual investment. Don't poke her into Ann Summers and bully her into cheese cutter mesh numbers that make her feel like a Sunday joint wrapped in string.

Find something you both like and that she feels comfortable in. Think of it as a dress rehearsal for the real deal. Take some photos of her in it, show them to her and be more enthusiastic about them than you’ve ever been about anything in your entire life.